Process for the coagulation of latexlike emulsions



Patented Sept. 27, 1932 uurrso STATES PATENT orr cz FRITZ SCHWEBDTEL, OF COLOGNE-LEM, GERMANY, ASEIGNOB "110 I. G. FABIBEN INDUSTRIE .AKTIENGESELLSCHAFT, OF FBANKI'OBT-ON-THE-HAIN, emxm PROCESS FOR THE COAGULATION OF LATEXLIKE EKULSIONB No Drawing. Application filed December 16, 1930, Serial No. 502,888, and in Germany December 28, 1929.

The present invention relates to the coagulation of latexlike emulsions, obtained by I the polymerization in emulsion of butadiene- (1.3), homologues and analogues thereof.

5 The artificial latexlikeli uids obtainable by polymerization of diole me in emulsion can frequently be coagulated by acid, much like the latex of natural rubber.

To this method is, however, attached the great technical disadvantage, that the emul sifying agent present in the latex remains in the coagulation product and can be removed therefrom only with difiiculty and in a costly manner, for example, by extraction with organic solvents.

and in contradistin'ction to natural latex the latices obtained by the polymerization of diolefines, which diolefines may be represented by the general formula as, and 01: meanin hydrogen or methyl, can be coagulated satisfactorily by the addition of an alkali metal'salt. The process of coagulation by means of salts possesses the great technical advantage over the coa lation. by means of acids that the emulsi ying agent can easily be removed and recovered from the coagulation product by washing,

thus avoiding the costly extraction above referred to.

A further advantage of: the process consists in the fact that by this means artificial latices can be coagulated which cannot be 00- agulated by acids. When diolefines are polymerized in emulsions obtained by the use of salts of alkylated naphthalene sulfonic acids, such as the sodium salt of isobutyl naphthalene sulfonic acid or by the use of so-called acid emulsifiers, such as the hydrochloric acid salts of pentadecyl- -glyoxalidine or of the w-diethylamino-4-ethoxysanilide of oleic I acid, the latexlike systems produced therefrom cannot be coagulated with acids, but can be coagulated with alkali metal salts. Suitable salts for the coagulation are alkali metal salts of inorganic or organic acids, such as,

'50 sodium-, potassium-, or ammonium-halides,-

In accordance with the present inventioncarbonates, sulfates, nitrates, phosphates, acetates, benzene sulfonates, naphthalene sulfonates and the like. The salts are with advantage added in the form of concentrated aqueous solutions. 5 The concentration and amount of the salt solution tobe employed depends not only on the quantity of the emulsifying agent, but also on the quantity of polymerization prod- .nct contained in the latexlike liquid. The on Example 1 100 parts by weight of latex, produced by the polymerization of butadiene-(L3) in emulsion by means of a sodium oleate solution and containing 24 parts by weight of polymerization product are coagulated imme iately and completely by the addition of 5 arts by weight of a saturated sodium ch oride solution. l

An analogous latex containing parts by weight of polymerization product requires for coagulation 12 parts by weight of a saturated sodium chloride. solution.

, Example 2 Y arts by weight'of a latex, produced by the polymerization of 2.3-dimethylbutadiene- (1.3) in emulsion by means of a 10% sodium oleate solution and containing 30 parts by weight of polymerization product are coagulated immediately and completely by the addition of 15 parts by weight of a saturated sodium acetate solution.

EwampZeS 100 parts by weight of a latex,'produced emulsion by means of a solution of'the sodium salt of isobutyl naphthalene sulfonic acid and containing parts by weight of polymerization product are coagulated immedlately and completely by the addition of 10 parts by weight of a saturated sodium carbonate solution.

Example 4 100 parts by weight of a latex, produced by the polymerization of butadiene-( 1.3) in emulsion by means of. a 3% solution of the hydrochloride of the w-diethylamino-4-ethoxy-a'nilide of oleic acid and containing 45 parts by weight of polymerization product are coagulated immediately by the addition of 5 parts by weight of a saturated disodium phosphate solution. I claim 1. The process which comprises coagulating a latexlike emulsion obtained by thepolymerization in emulsion of a diolefine hydrocarbon of the general formula om=o+ z=om wherein an and m stand for hydrogen or methyl, by adding thereto an alkali metal sa t.

2. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of a diolefine hydrocarbon of the general formula capo-( hem I. .2. wherein m, and x stand for hydrogen or methyl, by adding thereto an inorganic alkali meta salt.

3. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of a diolefine hydrocarbon of the general formula om= :=0H. I I] I] wherein an and as, stand for hydrogen or methyl, by adding thereto an alkali met-a1 halide.

4. The process which comprises coagulata latexlike emulsion obtained by the merization in emulsion of a diole carbon of the general formula:-

merization in emulsion of a diolefine methyl, by adding thereto an aqueous solution of an alkali metal salt.

6. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of a diolefine hydrocarbon of the general formula wherein ai and stand for hydrogen or methyl, by adding thereto a concentrated aqueous solution of an alkali metal salt.

7. The process which comprises coagulating a latexlike emulsion obtained by the poly- 1 merization in emulsion of a diolefine hydrocarbon of'the general formula 'wherein an and w stand for hydrogen or methyl, by adding thereto a, concentrated aqueous solution of an inorganic alkali metal salt.

8. The process which comprises coagulating a latexlike emulsion obtained by the polyt merization in emulsion of'a, diolefine hydrocarbon of the general formula I on.'= 3=on. 11 32 wherein an and m stand for hydrogen or methyhby adding thereto a concentrated aqueous solution of an alkali metal halide.

9. The process which comprises coagulat- 1 ing a latexlike emulsioh obtained b the polyne hydro- CH:=CC=CH2 L. I. wherein an and 02 stand for hydrogen or methyl, by addin thereto a concentrated aqueous solution 0 sodium chloride.

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10. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of butadiene (1.3) by adding thereto an alkali metal salt.

11. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of butadiene- (1.3) by adding thereto an inorganic alkali metal salt.

12. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of butadieneby adding thereto an alkali metal hal- 1 e.

13. The process which comprises coagulating a latexlike emulsion obtained by the polymerization in emulsion of butadiene- (1.3) .by adding thereto sodium chloride.

14. The process which comprises coagulating a latex-like emulsion obtained by the;

polymerization in emulsion of butadiene- (1.3) by adding thereto an aqueous solution of an alkali metal salt.

ous solution of an 15. The process which comprises coa lating a latexlike emulsion obtained by the polymerization in emulsion of butadiene- (1.3) by adding thereto a concentrated aqueous solution of an alkali metal salt.

process which comprises coagulating a latexlike emulsion obtained b the polymerization in emulsion of butadiene- (ill) by adding thereto a concentrated aquein'organic alkali metal salt. H. The process which comprises coagulating a l'atexlike emulsion obtained by the polymerization in emulsion of butadiene- (1L3) by adding thereto a concentrated aque' ous solution of an alkali metal halide.

18. The process which comprises coagu lating a latexlike emulsion obtained by the olymerization in emulsion of butadiene- (1L3) by adding thereto a concentrated aqueone solution of sodium chloride. ln testimony whereof, I afiix my signature. FRITZ SCHWERDTEL.

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